The Join In Stay In Fund will award grants of up to £50,000 and significant non-financial support from a behavioural science evaluation partner, for organisations to undertake Randomised Controlled Trials (RCTs) to understand which interventions work best in retaining volunteers who are 50 and over following a large one-off volunteering event. 
Nesta are inviting expressions of interest from organisations who are already experienced in mobilising large numbers of volunteers, particularly those who are aged 50 and over, in impact volunteering roles.
Nesta are looking to support eight to ten organisations from March 2017 to October 2017 to:
• Run a one-off impact volunteering event (on a single day) that draws in large numbers (at least 500 but ideally 750 to 1,000) of new volunteers aged 50 and over.
• Conduct RCTs to test one or two different retention approaches from the organisation’s norm to understand what is most effective in retaining volunteers who are 50 and over. This will involve being able to split the 500+ volunteers into two to three groups in a random way and conduct tests between May and October 2017.
• Monitor the take up of volunteering opportunities over a six-month period and analyse the data.
• Share the information on what works in retaining volunteers with others.
• A behavioural science evaluation partner will be in place to work with organisations to develop and assess the impact made through different retention approaches.
The desired outcomes of the Fund will be a significant number of people giving their time and energy to help others, alongside public services, as well as new insights about what works in retaining volunteers who are 50 and over.
This Fund is about both mobilising large numbers (500 plus) of volunteers (aged 50+) and then conducting RCTs to test what techniques work best to retain them. The fund will therefore be well suited to organisations that have a reliable pipeline of volunteering opportunities, with established procedures in place for assessing impact, in addition to being able to attract new volunteers to a large one-off event.
To apply submit an expression of interest from by 26 October 2016, 12:00. Following a selection process, the best applications from the expression of interest stage will be invited to a finalist event in London on 17 November 2016.
Nesta are seeking applications from not-for-profit (e.g. local authorities and charities) or social purpose organisations (e.g. social enterprises) who already deliver impact volunteering activities that provide public benefit. Organisations must operate and deliver their volunteering activities in England.
For further information and to apply, visit: www.nesta.org.uk/project/join-stay-fund